Radio antenna



Feb. 8, 1944. v lT 2,341,401

RADIO ANTENNA Filed Aug. 9', 1939 INVENTORY WESLEY J1 WHITE PatentedFeb. 8, 1944 RADIO ANTENNA Wesley J. White, Cleveland, Ohio, assignor toThe Radial-t Corporation, Cleveland, Ohio, a

corporation of Ohio Application August 9, 1939, Serial No. 289,154

2 Claims. (01. 250-33) i This invention relates to an antenna assemblyunit including a telescopicallyextensible aerial and a reel forextending and retracting the aerial.

An antenna of the general nature indicated above involves far more thanat first appears. The entire assembly must be designed electrically tomeet two conditions. First, the antenna proper, in addition to being aneilicient medium for receiving or sending radio signals must becompletely insulated from the metallic vehicle body on which it isnormally mounted. .Second, for appearance sake, the aerial whenretracted is contained within the body and even in an active positionhas parts electrically connected to it which are within the body. Suchparts of the assembly must be properly shielded to prevent the signalsfrom being interrupted by ignition noises and the like which might bepicked up.

In addition to the electrical features outlined above the unit must bevery easy to operate which means that the operating parts must not bindor jam. Reel operated antennae normally include a long guided flexiblemember and this has a tendency to bind in its confining case whichaggravates the mechanical problem present.

Further such antenna must be made available in large quantities at a lowcost of parts which are inexpensive and easily fabricated.

The chief object of the invention then is the provision of an operatingmechanism which will function smoothly and with a minimum of effort andwhich is not liable to become jammed or locked during use. Still anotherobject has been to provide an electrically efiicient antenna of minimumcost and number of parts.

, To the accomplishment of the foregoing and related ends, saidinvention, then, consists of the means hereinafter fully described andparticularly pointed out in the claims; the annexed drawing and thefollowing description setting forth in detail certain structureembodying the invention, such disclosed structure constituting, however,but one of various forms in which the principle of the invention may beused.

In said annexed drawing- Fig. 1 is a side elevation partly in section ofthe signal-carrying antenna employed with my invention;

Fig. 2 is a vertical section through the winding reel mechanismemployed;

Figs. 3 and 4 are sections through Fig. 2 as indicated by the lines 3-3and 4-4 thereon;

Fig. 5 is a side elevation partially in section of a modified form of myinvention; and

Fig.6 is a section through Fig. 5.as indicated by the line 6-6 thereon.

Referring now to Fig. 1, the aerial proper comprises a sleeve H) whichis bolted as at l2 to the vehicle body and is insulated therefrom toprevent the transmission of the antenna signals to the car body with aconsequent grounding thereof. A lead M from the base of the aerialconnects with the radio set to transmit the signals between the set andthe aerial. The sleeve I0 is necked inwardly as at IE to closely embracea second sleeve ll slidable therein.

The sleeve I1 is provided with a resilient spring member [8 at itsbottom portion which cooperates with the necked-in part IE to retain thesleeves in fixed relation with each other and also to prevent rattlingtherebetween. The sleeve I1 is necked in at I9 and slidably receives arod 20, which at its lower end is provided with a resilient springmember 2| similar to the member l8 and for the same purpose. A ball 22surmounts the rod 20.

In extending the antenna the rod is pushed upwardly by a flexible cable25, hereafter de scribed, which is soldered as at 26 to the end of therod.

As the rod 2 is pushed upwardly the member 2| ultimately engages ashoulder 2'! formed by the necked-in part 19 and then pulls the sleeveI! up until its member It comes into abutment with a similar shoulder 28of the neckedin portion 15 of the sleeve Ill. Electrical contact ismaintained between the sleeve and the rod and the lead-in connection I4to provide a continuous electrical unit.

The cable 25 is normally coiled about a reel 30 (Fig. 2) which isrotated by a hand crank 32. The reel is formed of a molded plastic disk33 of insulating material, as Bakelite. One flat face of the reel isformed with a helical recess 34 comprising several convolutionsextending about the axis of the reel, as indicated in Fig. 2. Thisrecess is adapted to accommodate the cable 25, which is secured at theinner end thereof at 35.

To hold the cable within the recess or passage a cover plate 3'! isprovided which lies closely adjacent the recessed face of the reel andprevents the cable from coming out of the recess except at a transverseslot 38 which is of a width suflicient to span all the convolutions oithe recess 34. The cable, which is normally coiled in the reel 33, isguided onto or oil of the reel from a corresponding convolution by theslot 38 as the handle 32 is turned. The cable leads from the reel to theinner end of the rod 20 passing through the antenna sleeves and asheath. A metallic sheath 40 encloses the cable from the end of thesleeve l until it passes within the reel. The sheath is of metallicconstruction and is grounded as indicated in Fig. 2. It is electricallyseparated from the sleeve [0 by the insulating washer M. The interior ofthe sheath is likewise insulated to prevent electrical contact betweenit and the cable with a consequent grounding of the antenna. Afunnel-shaped metallic cap 42, insulated on the inside, connects the endof the sheath adjacent-the reel and'a metallic grounded container 43which encloses the 'reel. This container surrounds the reel andcooperates with the sheath to prevent the wire 25 from picking upignition noises and the like from the car and transmitting them to theset. There "is of course noelectrical contact between the cableand-anypart of the sheath or the funnel-like member 42 or the enclosure 43.

A modified form of my invention is shown in Figs.'- and 6. Thiscomprises a cylindricalreel 50iormed of similar material to the reel 33which is provided with a continuous helical recess 52 extendingperipherally of the cylinder and adapted to receive the wire 25. Thewire is fastened at 53 into the end of the recess.

To guide the wire into the proper convolution of the recess and retainit therein an enclosing cover 54 formed of a moldedinsulating plastic,as the cover 31, is provided'in which is formed an-axially extendingslot 55. The slot 55 functions precisely as the slot 38 shown in Fig.3111 my preferred form of construction to guide the wire 25 onto and offof the reel.- A second enclosure 5! formed of sheet metal surrounds theentire reel and the cover or enclosure 54 to act as an electricalshield. This in turn is grounded tocut out ignition'noises and the likewhich might be picked up by thewire and transmitted to the antenna andthence'to the set. In like manner the sheath 40, which connects thereel'5ll and the sleeve I0, is formed identically with the sheath 40already described. In other words, it consists of a metallic exteriorsheath which is grounded to the vehicle frame and a layer of insulationinterposed between such sheath and the cable 25;

The knob 60 rotates the reel 5!] to extend or retract theaerial proper.As the handle of either the preferredor modified form of my inventionis: turned a cable will be either drawn into or unwound from thecorresponding reel. If it is unwound from the reel it-pushes on the rod20 toextend the antenna as above described. If, on the other hand, thecable is coiledonto the thereel the rod 20 is retracted and the antennais collapsed. The structure of my invention-may be installedin anydesired-place on a motor vehicle, as, for instance, adjacent the cowl-or in one of the bodypillarsr It will be seen from the foregoingdescription that I have provided a novel coil-up antenna system in whichthe antenna proper, including the flexible operating member is entirelyinsulated from an enclosing metallic case, which in turn is grounded tothe vehicle. It will further be apparent that the reel in either thepreferred or modified form is of such construction that no binding orlocking of the parts can take place as the antenna proper is extended orretracted. Also, in place of the cable 25 I may employ a flexible tapeor a solid flexible wire as well as the twisted cable shown.

Other modes of applying the principle of my invention may beemployedinstead of the one explained, change being made as regards the structureherein disclosed, provided the means statedby any of the followingclaims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

C1 In an extensible antenna adaptedto be mountedionza-motor vehicle, anantenna mem'ber adapted to be extended or retracted with respect to thevehicle body, a reel 'mounted for rotation adjacent the antenna, acontinuous guiding passage in'said reel comprising a series ofcircumferential convolutions extending about the axis of saidreel, aflexible connecting member secured at oneend to said antenna and at theother end coiled about said reel in the continuouspassage thereof, ametallic container enclosing said reel and electrically insulatedfromsaid reel and flexible member, said container having a funnel shapedcap secured thereto, anda tubular metallic sheath extending from saidcap to said antenna member, said sheath forming a guide for saidflexible member and being insulated from said flexible member and fromsaid antenna member and a ground connection for said sheath.

2-. In an extensible antenna adapted to be mountedon a motor vehicle, anantenna member adapted "to be extended or retracted with respecttothevehicle body, a reel mountedfor rotation adjacent the antenna, acontinuous guiding passage in'said reel comprising a series ofcircumferential convolutions extending about the axis of said reel, 2.flexible connecting member secured at-one end to said antenna and at theother end coiled about said reel in the continuous passage thereof, ametallic container enclosingsaid reel and electrically insulated fromsaid reel and flexible member, said container having a slot int-heperiphery thereof,- a hollowcap secured to said container andcommunicating with said slot, 9. tubular metallic sheath extending fromsaid "cap to said antenna member and in communication with said cap,said flexible member extending through said slot, cap and sheathandelectrically insul-atediromsaid sheath, and a ground-connection--forsaid sheath.

WESLEY J. WHITE.

